Method of sealing conduits



May 28, 1949. R B'ISHQP 2,202,631?

METHOD OF SEALING CONDUITS Filed Feb. 24, 1959 A ORNEYS Patented May 28,5.946 l UNITED STATES PATENT OFFICE 'METHOD OF SEALING connUr'rs RichardE. Bishop, South Orange, N. J., assignor to A. C. Horn & Company, LongIsland City, N. Y., a corporation of New York Application February 24,1939, Serial No. 258,207

Claims. (Cl. 174-111 v This invention relates to improvements inprepared on the job and applied, after which it methods of Sealing theends of il s through rapidly cures to form a permanent rugged seal.which electric cables and the like issue and the The incorporation ofthe fibrous rope with the product resulting therefrom. rubber materialhas the advantage in addition to o M r pe i c ly it is n o j f this invrendering the entire seal pliable, of absorbing the o tien to provide ap a al and at y simple moisture from the rubber composition during the mh f Sealing the Space in the s of c ncuring period, to facilitate arapid cure. This duits and the like through which electric cablesabsorption of moisture, however, is not so rapid issue consisting in theprocedure of forming a a to so sho t n th etting tim th t it, ill

seal therein of a suitable rubber composition and interfere ith thpreparation of a good w loosely woven ropes or strands of fibrousmaterial While a rubber plastic of this type is conductive such as jute,hemp and the like. while plastic, it becomes insulating when set,

It is among the objects of this invention to cured or vulcanized, andhas the distinct ability Provide a Sea] for the 9nd of a u t through ofclosely bonding to the rubber insulation of the which electric cablesissue mp oy a moldable cables and to the conduit walls when they have llP1851310 mass having a rubber base which is been primed. Where desiredsuitable vulcanizing Capable of setting of cu g and which is agents,accelerators, and/or anti-oxidents, as well ductive while plastic andinsulating when set and as inert filler materials, may be employed forwhich is then waterpro0f.. 1 their own purposes.

Anothe obj ct Subsidiary to that above is the Inaccordance with thisinvention seals of this attainment of a wa er-ti ht j t w n the type maybe rapidly made at relatively little excables and the COIldlllt wall andthe rubber seal ense, In some uses a, suitable rubber solvent wherein inthe case of rubber covered cables the may be employed as arrier f th rbb i set or cured mass is firmly bonded to the rubber gredient upon theevaporation of which a. practi- 25 insulation of the cables. cal seal issecured.

The othe Obj of this invention Will be ap- Referring to the drawing,there is illust ated parent from the following detailed description ofat; in a waiithrough which the conduit ll .issues, one embodimentthereof. which wall may be the foundation of a building,

This invention resides substantially in the the wall of a transformervault, or the like. In 3 combination, construction, arrangement,relative the case where the conduits H for example ex- 0. location ofparts, steps and series of steps, as tend fromatransformer vault in thestreet to the hereinafter disclosed. basement of an adjoining building,it is common This application is a continuation in part of .practice topitch the pipe toward the building so my co-pending application SerialNo. 179,377, that moisture will not collect therein.

filed December 11, 1937. a Under these conditions should the transformerg In the accompanying drawing: vault accumulate water up to the level ofthe Figure 1 is a vertical, longitudinal, central, conduit, it would runtherefrom into the building.

cross-sectional view through a conduit and cable For this reason amongothers, it is. desirable to assembly to be sealed in accordance withthis seal the conduit in the spaces around the cables invention,illustrating the first step of the which lie therein. These cables havebeen illus- 0 method. trated by the reference numeral H in the draw-Figure 2 is a similar view illustrating the ing as of the known leadedservice cable type second step thereof. having a weatherproof braidcovering as illus- Figure 3 is a final view illustrating the comtrated.plated product. Heretofore the conduits of this type have been I Inaccordance with this invention, the ends of sealed with putty but thisis unsatisfactory beconduits are sealed by using fibrous ropes and Acause it tends to crack and break away, especially rubber compositionssuch as latex which when since the workmen often stand or, sit on theexemployed as hereinafter disclosed, provide a seal posed cables whileworking. Various latex com- ,zo which strongly adheres to the definingboundaries pounds have been tried but it frequently happens of the sealand which are sufficiently pliant to that they are washed away ordestroyed before maintain the Seal under e Various temperature they areproperly set. In any event in the forms and moisture conditionsencountered in use. "commonly used it is hard to seal the conduits be-Furthermore, the rubber ingredient of the joint cause of their tendencyto flow before they set.

employed in such form that it may readily be In accordance with thisinvention a portion of I;

the fabric covering of, the cables is removed, as as the rubber tapewhich is commonly used on them as indicated at it. This will leaveexposed the rubber covered conductors which forms a good base for theseal as will become apparent later.

A mass of loosely woven fibrous rope is then packed in the end of theconduit around the conductors, as is clear from Figure 2. A verysuitable fibrous rope for this purpose isloosely woven jute, hemp,oakum, or the like.

The next step is to'then dip a loosely woven strand of jute or hemp inlatex or a rubber solution of the type referred to above'so as to bethoroughly coated with a thin layer thereof. The fibrous strand thuscoated is then packed in around the conductors, to fill up the remainderof the end of the conduit as illustrated at IS in Figure 3.

When desired the interior wall of the conduit in the area to be sealedmay be first primed with a suitable latex or rubber solution orcomposition to form a surface against which the rubber coated packingmay firmly bond. In those cases where the conductors after preparationas indicated in Figure 1 still have a rubber covering on them, it willbe seen that the rubber coated strands will also form an intimate bondtherewith.

The tightly packed rubber strands, as the rubber cures, weld or moldinto a unitary mass which forms a moistureproof plug completely sealingthe end of the tube. Thus although the plug is con ductive whileplastic, it becomes highly insulating when it has set or cured. Thisplug, however, is sufiiciently flexible and resilient so as to withstandthe various strains to which it is subjected because of temperaturechanges and the like, without opening up to form cracks through whichmoisture may pass. It will be seen that the strands carrying the rubbercoating are sufi'. ciently self-supporting while the rubber is curing soas not to work outof the joint. The curing pr ceeds rapidly because ofthe absorption oil moisture by the strand, but slowly enough so that thework can be readily accomplished without rushing.

A suitable latex concentrate for this purpose is one consisting ofapproximately 60% solid con tent mixed with a suitable cement such asaiumi nous cement in a ratio of one to one by weight. As pointed outabove, this mixture include terms such as equalizers, accelerators.and/or anti-oxidants, all of which are known in "he art in variousforms. Instead of a latex compo tlon of this type rubber cut with asuitable organic in organic solvent may be employed, a number of whichare well known in the art.

From. the hove description it will be apparent those in the art thatmodification in the details of the invention may be employed withoutwhen the coating sets.

accent? departure from the novel subject matter herein set forth. I donot, therefore, desire to be strictly limited by the disclosure butrather by the claims granted me.

What is claimed is: I

1. A method of sealing the end of a conduit, comprising the steps offorming a fibrous plug in and back of the end of the conduit, dippingloosely woven strands of a fibrous material in a liquid rubbercomposition capable of setting, and filling the space between the plugand the adjacent end of the conduit with the dipped strands while thecomposition thereon, is liquid to seal the end of the conduit.

2. A method of sealing the end of a conduit, comprising the steps offorming a fibrous plug in and back of the end of the conduit, dippingloose- -1y woven strands of a fibrous'material in a liquid latexcomposition capable of setting, and filling the space between the plugand the adjacent end of the conduit with the dipped strands while thecomposition thereon is liquid to seal the end of the conduit.

3. The method of sealing the end of a conduit through which one or moreelectric cables project, which comprises packing a body of fibrousmaterial in the conduit around the cables in back of the end of theconduit, dipping a loosely woven fibrous rope in a liquid rubber mixturecapable of setting, priming the inner wall of the end of the conduitwith a liquid rubber mixture, and

packing the rope while its coating is still liquid in the end of theconduit and around the cables to seal the end of the conduit.

4. A method of sealing the end of a conduit through which one or moreinsulated cables having rubber and fabric layers project, which com--prises removing the cable fabric layer to expose the rubber layer,packing a mass of fibrous material in the conduit around the cables, andseal.- ing the end of the'conduit with fibrous strands coated with aliquid rubber mixture while the rubber mixture on the strands is stillliquid, whereby the coated strands are bonded to the exposed rubberlayers of the cables.

5. A method oi! sealing the end of a conduit irom which issues; at leastone insulated cable having rubber and fabric insulating layers, whichcomprises removing the fabric layer from the cable adjacent the end ofthe conduit to expose the rubber layer, forming a plug of fibrousmaterial in the conduit around the cable, priming the inner wall of theconduit at the end, and sealing the end of the conduit by packingtherein a loose- 1y woven strand coated with a liquid rubber compositionwhile the composition is still liquid, the coating being capable ofsetting, and the packing being bonded to the rubber covering of thecable RICHARD E. BISHOP.

